Production system of high wear-resistant graphite copper sleeve for engineering machinery hydraulic system

Abstract

This invention discloses a production system for high wear-resistant graphite copper bushings for hydraulic systems of engineering machinery. The system includes a multi-station rotary table with a feeding station, a graphite hole processing station, a plasma activation station, a high-pressure pulse impregnation station, a gradient rolling station, a laser alloying station, and a detection and unloading station arranged sequentially along the circumference. A graphite hole processing unit, located at the graphite hole processing station, is used to process an array of graphite storage holes on the inner circumferential surface of the copper bushing substrate. A plasma activation unit, located at the plasma activation station, is used to perform low-temperature plasma activation treatment on the inner wall of the graphite storage holes. This invention's production system for high wear-resistant graphite copper bushings for hydraulic systems of engineering machinery solves the problems of insufficient interfacial bonding between graphite and the copper substrate, poor consistency due to multi-stage decentralized production, and lack of online closed-loop control in existing graphite copper bushing production.

Description

Technical Field

[0001] This invention belongs to the field of copper-based self-lubricating bearing manufacturing technology, specifically relating to a production system for high wear-resistant graphite copper bushings for hydraulic systems of engineering machinery. Background Technology

[0002] Graphite copper bushings are self-lubricating bearings with a copper alloy base and graphite lubricant embedded in the friction surface. They are widely used in articulated and support components of hydraulic systems in engineering machinery. The operating conditions of hydraulic systems in engineering machinery are characterized by high loads, high reciprocating frequencies, and dusty environments, which places high demands on the wear resistance and service life of graphite copper bushings.

[0003] Existing manufacturing processes for graphite copper bushings typically include steps such as copper bushing substrate machining, graphite hole drilling, graphite pressing, and surface finishing. These processes have the following shortcomings in practical applications: First, the graphite and the copper substrate are only mechanically interlocked and fixed, and the interfacial bonding force is limited. Under high pressure and reciprocating friction, the graphite is easy to fall out of the pores, resulting in lubrication failure and rapid wear. Second, each process is set up independently and produced in a decentralized manner. Transfer between processes is time-consuming and can easily introduce secondary pollution, making it difficult to guarantee product consistency. Third, the lack of effective online detection methods means that the graphite filling quality and interface bonding status cannot be fed back in real time, resulting in a lag in the adjustment of process parameters. Fourth, the hardness and wear resistance of the working surface of the copper bushing are limited, making it difficult to meet the long service life requirements under heavy load conditions.

[0004] Therefore, it is necessary to develop a high wear-resistant graphite copper sleeve production system that can improve the interfacial bonding between graphite and copper substrate, realize multi-process integrated production, and have online closed-loop control capabilities. Summary of the Invention

[0005] The main objective of this invention is to provide a high wear-resistant graphite copper bushing production system for hydraulic systems of engineering machinery, which solves the problems of insufficient bonding force between graphite and copper substrate, poor consistency due to multi-process decentralized production, and lack of online closed-loop control in the existing graphite copper bushing production.

[0006] Another objective of this invention is to provide a high wear-resistant graphite copper bushing production system for hydraulic systems of engineering machinery, which solves the problems of insufficient hardness and wear resistance of the working surface of the copper bushing and unreasonable distribution of graphite layer density, which makes it difficult to achieve both lubrication performance and anti-shedding performance.

[0007] To achieve the above objectives, the present invention provides a production system for high wear-resistant graphite copper bushings for hydraulic systems of engineering machinery, comprising: The multi-station rotary table is arranged circumferentially with a feeding station, a graphite hole processing station, a plasma activation station, a high-pressure pulse impregnation station, a gradient rolling station, a laser alloying station, and a detection and unloading station. A graphite hole processing unit is provided at the graphite hole processing station and is used to process graphite storage holes arranged in an array on the inner circumferential surface of the copper sleeve substrate. A plasma activation unit is provided at the plasma activation station to perform low-temperature plasma activation treatment on the inner wall of the graphite storage pore, so that the inner wall forms a micro-nano-level rough structure and introduces active groups. A high-pressure pulse impregnation unit is provided at the high-pressure pulse impregnation station and is used to press graphite lubricant into the activated graphite storage hole in a pulse pressurization manner. A gradient rolling unit is provided at the gradient rolling station to densify the impregnated graphite layer with a rolling force that increases along the axial direction of the copper sleeve, so that the graphite layer forms a gradient structure with increasing density from the bottom of the hole to the opening of the hole. A laser alloying unit is provided at the laser alloying station for performing laser surface alloying treatment on the inner peripheral working surface of the copper sleeve substrate, forming a gradient alloy layer containing tin phase and graphite phase on the inner peripheral working surface. An online detection unit is installed at the detection and unloading station to detect the graphite filling rate and interfacial bonding strength. The closed-loop control unit is connected to the graphite hole processing unit, plasma activation unit, high-pressure pulse impregnation unit, gradient rolling unit, laser alloying unit, and online detection unit respectively, and is used to adjust the process parameters of each unit according to the detection results of the online detection unit.

[0008] As a further preferred embodiment of the above technical solution, the plasma activation unit includes a vacuum chamber, an electrode assembly disposed within the vacuum chamber, and a gas supply module. The gas supply module is used to supply a mixed gas of argon and hydrogen into the vacuum chamber. The electrode assembly generates glow discharge in the mixed gas, thereby forming an activation modification layer on the inner wall of the graphite storage pore.

[0009] As a further preferred embodiment of the above technical solution, the high-pressure pulse impregnation unit includes an impregnation chamber, a graphite slurry supply module, and a pulse pressurization module. The pulse pressurization module is used to apply pulse pressure to the impregnation chamber, and the graphite slurry supply module is used to supply graphite slurry, which is a mixture of graphite powder and lubricating oil, to the impregnation chamber.

[0010] As a further preferred embodiment of the above technical solution, the gradient rolling unit includes a rolling head and a linear drive mechanism for driving the rolling head to reciprocate along the axial direction of the copper sleeve. The rolling head has a plurality of rolling rollers arranged axially, and the diameter of each rolling roller increases from one end to the other along the copper sleeve, so that the rolling pressure applied by each rolling roller to the graphite layer increases axially.

[0011] As a further preferred embodiment of the above technical solution, the laser alloying unit includes a laser, a powder feeding nozzle, and a scanning galvanometer. The powder feeding nozzle is used to deliver tin alloy powder to the inner peripheral working surface of the copper sleeve. The laser beam output by the laser is deflected by the scanning galvanometer and scans the inner peripheral working surface, so that the tin alloy powder is fused with the surface layer of the copper sleeve substrate to form the gradient alloy layer.

[0012] As a further preferred embodiment of the above technical solution, the online detection unit includes an eddy current detection probe and an ultrasonic detection probe. The eddy current detection probe is used to detect the graphite filling rate, and the ultrasonic detection probe is used to detect the interfacial bonding strength between graphite and the copper substrate. The online detection unit also includes a marking module for marking copper sleeves that fail the test.

[0013] As a further preferred technical solution of the above technical solution, each station of the multi-station turntable is provided with a clamp for holding the copper sleeve substrate. The clamp includes an expansion sleeve mandrel and a hydraulic cylinder for driving the expansion sleeve mandrel to expand and contract. The outer peripheral surface of the expansion sleeve mandrel is provided with an elastic expansion sleeve that is adapted to the inner peripheral surface of the copper sleeve substrate.

[0014] As a further preferred embodiment of the above technical solution, the closed-loop control unit includes a data acquisition module, a parameter comparison module, and an instruction output module. The data acquisition module is used to acquire the graphite filling rate and interface bonding strength data output by the online detection unit. The parameter comparison module is used to compare the data with a preset threshold. When the graphite filling rate is lower than the preset filling rate threshold, the instruction output module outputs an instruction to the high-pressure pulse impregnation unit to increase the pulse pressure or extend the impregnation time. When the interface bonding strength is lower than the preset strength threshold, the instruction output module outputs an instruction to the plasma activation unit to extend the activation time or increase the activation power.

[0015] As a further preferred embodiment of the above technical solution, the graphite hole processing unit includes a CNC drilling spindle and a deburring tool. The CNC drilling spindle is used to drill the graphite storage hole on the inner circumferential surface of the copper sleeve substrate, and the deburring tool is used to remove burrs from the opening of the graphite storage hole.

[0016] As a further preferred technical solution to the above technical solution, the system generation process is as follows: Step S1, Loading: The copper bushing substrate is clamped on the fixture of the multi-station turntable, and the turntable rotates to allow the copper bushing substrate to enter each station in sequence. Step S2, Graphite Hole Machining: At the graphite hole machining station, the graphite hole machining unit processes graphite storage holes arranged in an array on the inner circumferential surface of the copper sleeve substrate and removes burrs from the hole openings. Step S3, Plasma Activation: At the plasma activation station, the inner wall of the graphite storage pore is subjected to low-temperature plasma activation treatment by the plasma activation unit, so that the inner wall forms a micro-nano-level rough structure and introduces active groups. Step S4, High-pressure pulse impregnation: At the high-pressure pulse impregnation station, the high-pressure pulse impregnation unit pressurizes the graphite lubricant into the activated graphite storage hole by pulse pressure. Step S5, Gradient Rolling Densification: At the gradient rolling station, the gradient rolling unit densifies the impregnated graphite layer with a rolling force that increases along the axial direction of the copper sleeve, so that the graphite layer forms a gradient structure with increasing density from the bottom of the hole to the opening of the hole. Step S6, Laser Surface Alloying: In the laser alloying station, the laser alloying unit performs laser surface alloying treatment on the inner peripheral working surface of the copper sleeve substrate, forming a gradient alloy layer containing tin phase and graphite phase on the inner peripheral working surface. Step S7, Online Inspection and Unloading: At the inspection and unloading station, the online inspection unit detects the graphite filling rate and interface bonding strength. The closed-loop control unit adjusts the process parameters of each unit according to the inspection results. Qualified products are unloaded, and unqualified products are marked before unloading.

[0017] The beneficial effects of this invention are as follows: First, the present invention uses a plasma activation unit to perform low-temperature plasma activation on the inner wall of the graphite storage pore, forming a micro-nano-level rough structure and active groups on the pore wall. Then, high-voltage pulse impregnation is used to press graphite lubricant into the pore. The activated pore wall and graphite form an interface bond with mechanical interlocking and chemical adsorption synergy, which is beneficial to improve the interface bond strength between graphite and copper substrate and reduce the risk of graphite shedding.

[0018] Secondly, the present invention densifies the graphite layer by using a gradient rolling unit with an axially increasing rolling force, so that the graphite layer forms a gradient structure with increasing density from the bottom of the hole to the opening. The high-density graphite layer at the opening is beneficial to resisting frictional shear and reducing shedding, while the relatively low-density graphite layer at the bottom of the hole is beneficial to the storage and slow release of graphite lubricant, thus taking into account both anti-shedding performance and continuous lubrication performance.

[0019] Third, the present invention forms a gradient alloy layer containing tin phase and graphite phase on the inner working surface of the copper bushing through a laser alloying unit. The tin phase is beneficial to improving the hardness and load-bearing capacity of the working surface, while the graphite phase is beneficial to maintaining self-lubricating properties. The gradient structure is beneficial to mitigating the sudden hardness change between the alloy layer and the substrate and reducing interlayer peeling, thereby improving the wear resistance and service life of the copper bushing.

[0020] Fourth, this invention integrates graphite hole processing, plasma activation, high-pressure pulse impregnation, gradient rolling, laser alloying, and inspection and blanking onto a single turntable through a multi-station turntable, realizing continuous production of single-piece flow. This helps reduce inter-process transfer and secondary pollution, and improves production efficiency and product consistency.

[0021] Fifth, this invention uses an online detection unit to detect the graphite filling rate and interfacial bonding strength in real time, and the closed-loop control unit dynamically adjusts the process parameters of each unit based on the detection results. This helps to detect and correct process deviations in a timely manner, thereby improving product qualification rate and quality stability. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the system structure of the present invention.

[0023] Figure 2 This is a schematic diagram of the method flow of the present invention. Detailed Implementation

[0024] The following description is intended to disclose the present invention and enable those skilled in the art to implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art. The basic principles of the invention defined in the following description can be applied to other embodiments, modifications, improvements, equivalents, and other technical solutions that do not depart from the spirit and scope of the invention.

[0025] In the preferred embodiments of the present invention, those skilled in the art should note that the hydraulic systems for engineering machinery involved in the present invention can be considered as prior art.

[0026] Preferred embodiment.

[0027] like Figure 1 As shown, this invention discloses a production system for high wear-resistant graphite copper bushings used in hydraulic systems of engineering machinery, comprising: A multi-station rotary table is arranged circumferentially with a loading station, a graphite hole processing station, a plasma activation station, a high-pressure pulse impregnation station, a gradient rolling station, a laser alloying station, and a detection and unloading station. Each station of the multi-station rotary table is equipped with a fixture for clamping the copper sleeve substrate. The fixture includes an expansion sleeve mandrel and a hydraulic cylinder for driving the expansion sleeve mandrel to expand and contract. The outer circumferential surface of the expansion sleeve mandrel is provided with an elastic expansion sleeve that is adapted to the inner circumferential surface of the copper sleeve substrate. During clamping, the copper sleeve substrate is sleeved on the expansion sleeve mandrel, and the hydraulic cylinder drives the expansion sleeve mandrel to move axially, causing the elastic expansion sleeve to expand radially, thereby tightening the copper sleeve substrate from the inside.

[0028] A graphite hole machining unit, located at the graphite hole machining station, is used to machine an array of graphite storage holes on the inner circumferential surface of the copper sleeve substrate. The unit includes a CNC drilling spindle and a deburring tool. The CNC drilling spindle drills the graphite storage holes on the inner circumferential surface of the copper sleeve substrate, and the deburring tool removes burrs from the hole openings to prevent them from affecting subsequent graphite impregnation and interface bonding. The diameter of the graphite storage holes is 2 to 8 mm, the depth is 1 to 4 mm, and the spacing between adjacent holes is 5 to 15 mm. In this embodiment, the graphite storage holes are arranged in an equilateral triangular array to ensure uniform distribution of graphite on the inner circumferential surface of the copper sleeve.

[0029] A plasma activation unit, located at the plasma activation station, is used to perform low-temperature plasma activation treatment on the inner wall of the graphite reservoir, forming a micro-nano-scale rough structure and introducing active groups. The plasma activation unit includes a vacuum chamber, an electrode assembly disposed within the vacuum chamber, and a gas supply module. The gas supply module supplies a mixture of argon and hydrogen to the vacuum chamber. The electrode assembly generates a glow discharge in the mixed gas, forming an activated modified layer with a thickness of 1 to 5 micrometers on the inner wall of the graphite reservoir. This activated modified layer has a micro-nano-scale rough structure and introduces oxygen-containing active groups, which is beneficial for the subsequent wetting and adhesion of graphite slurry to the pore wall.

[0030] A high-pressure pulse impregnation unit, located at the high-pressure pulse impregnation station, is used to inject graphite lubricant into activated graphite reservoirs using pulsed pressure. The high-pressure pulse impregnation unit includes an impregnation chamber, a graphite slurry supply module, and a pulsed pressure module. The pulsed pressure module applies pulsed pressure with a frequency of 1 to 10 Hz and a peak pressure of 50 to 200 MPa to the impregnation chamber. The alternating pulse pressure facilitates the full penetration of the graphite slurry into the micro-nano-scale rough structure of the graphite reservoir, improving the graphite filling rate. The graphite slurry supply module supplies the impregnation chamber with a graphite slurry composed of graphite powder with a particle size of 1 to 50 micrometers mixed with lubricating oil.

[0031] A gradient rolling unit, disposed at the gradient rolling station, is used to densify the impregnated graphite layer with a rolling pressure that increases along the axial direction of the copper sleeve, forming a gradient structure in which the density of the graphite layer increases from the bottom of the hole to the opening. The gradient rolling unit includes a rolling head and a linear drive mechanism that drives the rolling head to reciprocate along the axial direction of the copper sleeve. The rolling head has multiple rolling rollers arranged axially, the diameter of each rolling roller increasing from one end to the other along the copper sleeve, so that the rolling pressure applied to the graphite layer by each rolling roller increases axially. The rolling head reciprocates 1 to 3 times along the axial direction of the copper sleeve, forming a gradient structure in which the density of the graphite layer increases from the bottom of the hole to the opening.

[0032] A laser alloying unit, located at the laser alloying station, is used to perform laser surface alloying treatment on the inner circumferential working surface of the copper sleeve substrate, forming a gradient alloy layer containing tin and graphite phases on the inner circumferential working surface. The laser alloying unit includes a laser, a powder feeding nozzle, and a scanning galvanometer. The powder feeding nozzle delivers tin alloy powder to the inner circumferential working surface of the copper sleeve. The laser beam output from the laser is deflected by the scanning galvanometer and scans the inner circumferential working surface, causing the tin alloy powder to fuse with the surface layer of the copper sleeve substrate to form the gradient alloy layer. The thickness of the gradient alloy layer is 20 to 100 micrometers. The tin content gradually decreases from the surface towards the substrate in this gradient alloy layer, which is beneficial for improving the hardness and wear resistance of the copper sleeve working surface.

[0033] An online inspection unit, located at the inspection and unloading station, is used to inspect the graphite filling rate and the interfacial bonding strength. The online inspection unit includes an eddy current testing probe and an ultrasonic testing probe. The eddy current testing probe is used to inspect the graphite filling rate, and the ultrasonic testing probe is used to inspect the interfacial bonding strength between the graphite and the copper substrate. The online inspection unit also includes a marking module for marking unqualified copper sleeves for subsequent sorting.

[0034] The closed-loop control unit is connected to the graphite hole processing unit, plasma activation unit, high-pressure pulse impregnation unit, gradient rolling unit, laser alloying unit, and online detection unit respectively, and is used to adjust the process parameters of each unit according to the detection results of the online detection unit.

[0035] The closed-loop control unit includes a data acquisition module, a parameter comparison module, and an instruction output module. The data acquisition module is used to acquire the graphite filling rate and interface bonding strength data output by the online detection unit. The parameter comparison module is used to compare the data with preset thresholds. When the graphite filling rate is lower than the preset filling rate threshold, the instruction output module outputs an instruction to the high-pressure pulse impregnation unit to increase the pulse pressure or extend the impregnation time. When the interface bonding strength is lower than the preset strength threshold, the instruction output module outputs an instruction to the plasma activation unit to extend the activation time or increase the activation power.

[0036] like Figure 2 As shown, the system generation process is as follows: Step S1, Loading: The copper bushing substrate is clamped on the fixture of the multi-station turntable, and the turntable rotates to allow the copper bushing substrate to enter each station in sequence. Step S2, Graphite Hole Machining: At the graphite hole machining station, the graphite hole machining unit processes graphite storage holes arranged in an array on the inner circumferential surface of the copper sleeve substrate and removes burrs from the hole openings. Step S3, Plasma Activation: At the plasma activation station, the inner wall of the graphite storage pore is subjected to low-temperature plasma activation treatment by the plasma activation unit, so that the inner wall forms a micro-nano-level rough structure and introduces active groups. Step S4, High-pressure pulse impregnation: At the high-pressure pulse impregnation station, the high-pressure pulse impregnation unit pressurizes the graphite lubricant into the activated graphite storage hole by pulse pressure. Step S5, Gradient Rolling Densification: At the gradient rolling station, the gradient rolling unit densifies the impregnated graphite layer with a rolling force that increases along the axial direction of the copper sleeve, so that the graphite layer forms a gradient structure with increasing density from the bottom of the hole to the opening of the hole. Step S6, Laser Surface Alloying: In the laser alloying station, the laser alloying unit performs laser surface alloying treatment on the inner peripheral working surface of the copper sleeve substrate, forming a gradient alloy layer containing tin phase and graphite phase on the inner peripheral working surface. Step S7, Online Inspection and Unloading: At the inspection and unloading station, the online inspection unit detects the graphite filling rate and interface bonding strength. The closed-loop control unit adjusts the process parameters of each unit according to the inspection results. Qualified products are unloaded, and unqualified products are marked before unloading.

[0037] It is worth mentioning that the technical features of the hydraulic system for engineering machinery involved in this patent application should be regarded as prior art. The specific structure, working principle, and possible control methods and spatial arrangement of these technical features can be adopted using conventional choices in the field, and should not be regarded as the inventive point of this patent. This patent will not be further elaborated in detail.

[0038] For those skilled in the art, modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention should be included within the protection scope of this invention.

Claims

1. A production system for high wear-resistant graphite copper bushings for hydraulic systems of engineering machinery, characterized in that, include: The multi-station rotary table is arranged circumferentially with a feeding station, a graphite hole processing station, a plasma activation station, a high-pressure pulse impregnation station, a gradient rolling station, a laser alloying station, and a detection and unloading station. A graphite hole processing unit is provided at the graphite hole processing station and is used to process graphite storage holes arranged in an array on the inner circumferential surface of the copper sleeve substrate. A plasma activation unit is provided at the plasma activation station to perform low-temperature plasma activation treatment on the inner wall of the graphite storage pore, so that the inner wall forms a micro-nano-level rough structure and introduces active groups. A high-pressure pulse impregnation unit is provided at the high-pressure pulse impregnation station and is used to press graphite lubricant into the activated graphite storage hole in a pulse pressurization manner. A gradient rolling unit is provided at the gradient rolling station to densify the impregnated graphite layer with a rolling force that increases along the axial direction of the copper sleeve, so that the graphite layer forms a gradient structure with increasing density from the bottom of the hole to the opening of the hole. A laser alloying unit is provided at the laser alloying station for performing laser surface alloying treatment on the inner peripheral working surface of the copper sleeve substrate, forming a gradient alloy layer containing tin phase and graphite phase on the inner peripheral working surface. An online detection unit is installed at the detection and unloading station to detect the graphite filling rate and interfacial bonding strength. The closed-loop control unit is connected to the graphite hole processing unit, plasma activation unit, high-pressure pulse impregnation unit, gradient rolling unit, laser alloying unit, and online detection unit respectively, and is used to adjust the process parameters of each unit according to the detection results of the online detection unit.

2. The high wear-resistant graphite copper bushing production system for hydraulic systems of engineering machinery according to claim 1, characterized in that, The plasma activation unit includes a vacuum chamber, an electrode assembly disposed within the vacuum chamber, and a gas supply module. The gas supply module is used to supply a mixture of argon and hydrogen into the vacuum chamber. The electrode assembly generates glow discharge in the mixture, thereby forming an activation modification layer with a thickness of 1 to 5 micrometers on the inner wall of the graphite storage pore.

3. The high wear-resistant graphite copper bushing production system for hydraulic systems of engineering machinery according to claim 1, characterized in that, The high-pressure pulse impregnation unit includes an impregnation chamber, a graphite slurry supply module, and a pulse pressurization module. The pulse pressurization module is used to apply a pulse pressure with a frequency of 1 to 10 Hz and a peak pressure of 50 to 200 MPa to the impregnation chamber. The graphite slurry supply module is used to supply the impregnation chamber with a graphite slurry made of graphite powder with a particle size of 1 to 50 micrometers and lubricating oil.

4. A high wear-resistant graphite copper bushing production system for hydraulic systems of engineering machinery according to claim 1, characterized in that, The gradient rolling unit includes a rolling head and a linear drive mechanism that drives the rolling head to reciprocate along the axial direction of the copper sleeve. The rolling head has a plurality of rolling rollers arranged axially, and the diameter of each rolling roller increases from one end to the other along the copper sleeve, so that the rolling pressure applied by each rolling roller to the graphite layer increases axially.

5. A high wear-resistant graphite copper bushing production system for hydraulic systems of engineering machinery according to claim 1, characterized in that, The laser alloying unit includes a laser, a powder feeding nozzle, and a scanning galvanometer. The powder feeding nozzle is used to deliver tin alloy powder to the inner peripheral working surface of the copper sleeve. The laser beam output by the laser is deflected by the scanning galvanometer and scans the inner peripheral working surface, so that the tin alloy powder is fused with the surface layer of the copper sleeve substrate to form the gradient alloy layer. The thickness of the gradient alloy layer is 20 to 100 micrometers.

6. A high wear-resistant graphite copper bushing production system for hydraulic systems of engineering machinery according to claim 1, characterized in that, The online testing unit includes an eddy current testing probe and an ultrasonic testing probe. The eddy current testing probe is used to detect the graphite filling rate, and the ultrasonic testing probe is used to detect the interfacial bonding strength between graphite and the copper substrate. The online testing unit also includes a marking module for marking copper sleeves that fail the test.

7. A high wear-resistant graphite copper bushing production system for hydraulic systems of engineering machinery according to claim 1, characterized in that, Each station of the multi-station turntable is equipped with a clamp for holding the copper sleeve substrate. The clamp includes an expansion sleeve mandrel and a hydraulic cylinder for driving the expansion sleeve mandrel to expand and contract. The outer circumferential surface of the expansion sleeve mandrel is provided with an elastic expansion sleeve that is adapted to the inner circumferential surface of the copper sleeve substrate.

8. A high wear-resistant graphite copper bushing production system for hydraulic systems of engineering machinery according to claim 1, characterized in that, The closed-loop control unit includes a data acquisition module, a parameter comparison module, and an instruction output module. The data acquisition module is used to acquire the graphite filling rate and interface bonding strength data output by the online detection unit. The parameter comparison module is used to compare the data with preset thresholds. When the graphite filling rate is lower than the preset filling rate threshold, the instruction output module outputs an instruction to the high-pressure pulse impregnation unit to increase the pulse pressure or extend the impregnation time. When the interface bonding strength is lower than the preset strength threshold, the instruction output module outputs an instruction to the plasma activation unit to extend the activation time or increase the activation power.

9. A high wear-resistant graphite copper bushing production system for hydraulic systems of engineering machinery according to claim 1, characterized in that, The graphite hole machining unit includes a CNC drilling spindle and a deburring tool. The CNC drilling spindle is used to drill the graphite storage hole on the inner circumferential surface of the copper sleeve substrate. The deburring tool is used to remove burrs from the opening of the graphite storage hole. The diameter of the graphite storage hole is 2 to 8 mm, the depth is 1 to 4 mm, and the spacing between adjacent graphite storage holes is 5 to 15 mm.

10. A high wear-resistant graphite copper bushing production system for hydraulic systems of engineering machinery according to claim 1, characterized in that, The system generation process is as follows: Step S1, Loading: The copper bushing substrate is clamped on the fixture of the multi-station turntable, and the turntable rotates to allow the copper bushing substrate to enter each station in sequence. Step S2, Graphite Hole Machining: At the graphite hole machining station, the graphite hole machining unit processes graphite storage holes arranged in an array on the inner circumferential surface of the copper sleeve substrate and removes burrs from the hole openings. Step S3, Plasma Activation: At the plasma activation station, the inner wall of the graphite storage pore is subjected to low-temperature plasma activation treatment by the plasma activation unit, so that the inner wall forms a micro-nano-level rough structure and introduces active groups. Step S4, High-pressure pulse impregnation: At the high-pressure pulse impregnation station, the high-pressure pulse impregnation unit pressurizes the graphite lubricant into the activated graphite storage hole by pulse pressure. Step S5, Gradient Rolling Densification: At the gradient rolling station, the gradient rolling unit densifies the impregnated graphite layer with a rolling force that increases along the axial direction of the copper sleeve, so that the graphite layer forms a gradient structure with increasing density from the bottom of the hole to the opening of the hole. Step S6, Laser Surface Alloying: In the laser alloying station, the laser alloying unit performs laser surface alloying treatment on the inner peripheral working surface of the copper sleeve substrate, forming a gradient alloy layer containing tin phase and graphite phase on the inner peripheral working surface. Step S7, Online Inspection and Unloading: At the inspection and unloading station, the online inspection unit detects the graphite filling rate and interface bonding strength. The closed-loop control unit adjusts the process parameters of each unit according to the inspection results. Qualified products are unloaded, and unqualified products are marked before unloading.

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